Sniffing Position Improves Pharyngeal Airway Patency in Anesthetized Patients with Obstructive Sleep Apnea

Abstract

Sniffing position structurally improves maintenance of the passive pharyngeal airway in patients with obstructive sleep apnea and may be beneficial for both mask ventilation and tracheal intubation during anesthesia induction.

Optimising the unprotected airway with a prototype Jaw‐Thrust‐Device – a prospective randomised cross‐over study

“…first nasopharyngeal airway, second oropharyngeal airway, third the Esmarch manoeuvre, and last the JawThrust-Device). Performing four of four different tests without repetition in each patient produces 24 different combinations of order in which the tests can be performed (factorial [4] = 24). One of these 24 combinations was used for each of the first 24 patients, followed by randomised allocation to each of the subsequent 24 patients; combinations of the last two patients were drawn by lots.…”

“…The standard manoeuvre to solve these challenges is to use the Esmarch technique (bimanual jaw-thrust) of pulling the mandible in front of the maxilla [2,3]. This manoeuvre can be further improved by extending the patient's head on their flexed neck; the so-called 'sniffing the morning air' position [4]. Unfortunately, the Esmarch manoeuvre may be inadequate in some patients, particularly those who are edentulous or obese [5,6].…”

A reply

“…This allows a greater degree of head extension in the sniffing position and subsequently may be associated with better mask ventilation. The sniffing position, which is the recommended position for direct laryngoscopy, was also found endoscopically to improve pharyngeal patency during bag-andmask ventilation in fully paralysed patients when compared with the neutral position [4].…”

“…There was no mention why they changed from one to the other. A literature search shows that the interchangeability of recorded pain intensity measured using the two scales has been studied and the findings contentious [2][3][4]. Only 87 participants completed their pain diary fully.…”

Morbid Obesity and Obstructive Sleep Apnea: The Challenging Link

“…For example, under propofol/ vecuronium anesthesia, moving the patient from the supine to the sitting position improved (enlarged) both retropalatal and retroglossal regions in anesthetized and paralyzed patients with OSA, indicating that the structural properties of the passive pharynx were improved [12]. Second, and perhaps a bit easier to implement, is to extend the neck, enhancing the "sniffing" position for improved pharyngeal airway patency in OSA patients [27]. Insertion of the LMA ProSeal TM has been shown to be an effective temporary ventilation device before laryngoscopic-guided tracheal intubation in MO patients [28].…”